The highest optical zoom factor of an ordinary digital camera can reach more than 30 times, but it is meaningless to study this data, because the higher the zoom factor, the worse the image quality, so the professional-grade lenses of SLR cameras are designed to maximize the To ensure image quality, the zoom factor will generally not exceed 3 times. Lenses with large zoom ratios (such as 18-200mm) are used in ordinary cheap lenses.